Conventionally, as a contact switching device, as described in Japanese Patent Application Laid-Open No. 2009-230920, there has been a contact device including a contact block that contains, in a sealed container, fixed terminals having fixed contact portions and a movable contactor having movable contact portions that contact and depart from the fixed contact portions, a movable shaft with the movable contactor fixed to one end side thereof, a movable iron core fixed to another end side of the movable shaft, a fixed iron core that is inserted on the movable shaft to be opposed to the movable iron core, a drive block that generates a magnetic attraction force between both the iron cores to move the movable iron core in a direction where the movable iron core hits the fixed iron core, a return spring that biases the movable iron core in a direction where the movable contact portions depart from the fixed contact portions, a contact pressure spring that biases the movable contactor in a direction where the movable contact portions abut on the fixed contact portions, a bottomed cylindrical portion containing both the iron cores, a first bonding member made of a metal material that the fixed iron core adheres to, and is airtightly bonded to the bottomed cylindrical portion, a second bonding member made of a metal material that is airtightly bonded to the sealed container and the first bonding member to form a sealed space to contain both the contact portions and both the iron cores, and an insulating member that insulates arc generated between both the contact portions, and a bonding portion between the sealed container and the second bonding member, wherein the insulating member is disposed between the movable contactor and the first bonding member, in the contact pressure spring, one end portion thereof abuts on the movable contactor and another end portion thereof abuts on the insulating member, and the contact pressure spring is disposed in a compressed state between the movable contactor and the insulating member, in the return spring, one end portion thereof abuts on the movable iron core and another end portion thereof abuts on the insulating member, and the return spring is disposed in a compressed state between the movable iron core and the insulating member, and the return spring has a higher spring coefficient than the contact pressure spring.
In the above-described contact device, as illustrated in FIG. 1, fixed terminals 11 are inserted into through-holes 10a provided in a sealed container 10 made of a thermally-resistant material such as ceramic, and are airtightly bonded by brazing.